That's right. Taxing or taking all of the wealth from the super rich does not work, exactly because of math. Taxing a fraction of wealth, like property taxes, works because it's repeatable, which is essential to a tax revenue stream. Graduated income taxes also work, for the same reason, they are repeatable and continue to contribute to the tax revenue stream.

Taking all of a person's wealth would probably dash the motivation to succeed for many. I doubt it would affect the super rich as much. These are people who are driven. Being super rich is just a by product of their drive to build, build an empire of some kind. I think if all their wealth was taken, they would just begin building their next empire, starting the very next day. It's just how they are, and I'm not suggesting we take all their wealth. As pointed out above, it's counter-productive.

Getting back to free college; it's a bad idea for a number of reasons. First off, "there's no such thing as a free lunch." (Milton Freedman) College gets paid for one way or another. If gov't picks up the tab, then there is no incentive for colleges to attempt to hold down cost increases. As it is, college costs have increased at an even higher rate than medical and health costs in the U.S. Technology is one reason I suppose, but status is another. It's really important at the country club I don't belong to, to brag about how ridiculously much I spend on my kid's college education. Stanford, Harvard, Yale, and all the Ivy League and similar schools do this. By charging the rich these high college costs, the schools are able to create their own system of socialism and offer scholarships to high aptitude students whose parents aren't rich. In effect, rich parents helped pay for my kids' college educations, and in return, those rich parents got the bragging rights at their country club.

There are several ways to hold down college costs. Student loan forgiveness probably isn't one of the best ways because it removes the incentive for a college to hold down its costs.